Write the features that distinguish between the two

a. Plasma and Serum

b. Open and closed circulatory system

c. Sino-atrial node and Atrio-ventricular node

What is the significance of hepatic portal system in the circulatory system?

Explain the functional significance of lymphatic system?

Thrombocytes are essential for coagulation of blood. Comment.

Answer the following

a. Name the major site where RBCs are formed.

b. Which part of heart is responsible for initiating and maintaining its rhythmic activity?

c. What is specific in the heart of crocodiles among reptilians?